The 303 is still saleable in unmodified form, so I would offload it.
The single supply regulator is probably the weakest part of the design.
Fitting high speed transistors in those amazing triples is asking for trouble.
The single supply regulator is probably the weakest part of the design.
Fitting high speed transistors in those amazing triples is asking for trouble.
Alaska said:Well it looks like ill be building a gainclone some time soon then
Thanks for all the input everyone!
To all those who sugested I used the qaud 303 case to house a gainclone, I could never bring my self to gainclone my quad 303 but id be lying if I said the thought had never crossed my mind.
You were going to paint it white?, but draw the line at replacing the insides? - interesting line you draw
Shoog said:
Oh, I don't know...
This is how Quad themselves did it in the 306, 520f and probably others. Works well...
Having said that, you'll need to check the output voltage of the 303 transformer - it might exceed the maximum allowable for the chips. I'd guess that 50V RMS would be a safe limit, but it's up to the reader to satisfy themselves!
Attachments
For sure, build a Gainclone is far better ! 😉
You can build it with the power that you want, and the quality that you want too. The most simple and cheaper schematic with a 3886 will surprise you with the quality! 🙂
Build a Gainclone with lots of care, and do it right since the beginning, choosing the right supply and heatsink, to avoid any kind of problems when using it daily!
You can build it with the power that you want, and the quality that you want too. The most simple and cheaper schematic with a 3886 will surprise you with the quality! 🙂
Build a Gainclone with lots of care, and do it right since the beginning, choosing the right supply and heatsink, to avoid any kind of problems when using it daily!
Q 303 - Gainclone
I sincerely hope that this is not seriously a comparison of a Quad 303 and a gainclone.
In MY honest opinion a gainclone ( I made a few) is quality wise miles away from a Quad 303, One i have owned for about 20 years now (purchased second hand.... and had it serviced (read clean and put new gold plated connectors in it) one time.
Personnaly ( i said it twice now) the sound of a quad 303 and maybe also of a 33 is far superior to my gainclone(s)
it is simply not compareable!!!!!!!
If i say so myself, it's like the difference between sitting in a Bentley (with driver) and driving a Camry yourselves...
This is MY opinion of course!
Jean-Pierre
I sincerely hope that this is not seriously a comparison of a Quad 303 and a gainclone.
In MY honest opinion a gainclone ( I made a few) is quality wise miles away from a Quad 303, One i have owned for about 20 years now (purchased second hand.... and had it serviced (read clean and put new gold plated connectors in it) one time.
Personnaly ( i said it twice now) the sound of a quad 303 and maybe also of a 33 is far superior to my gainclone(s)
it is simply not compareable!!!!!!!
If i say so myself, it's like the difference between sitting in a Bentley (with driver) and driving a Camry yourselves...
This is MY opinion of course!
Jean-Pierre
If you like soft woolley 70's sounds then I would agree with your statement. Otherwise a well executed Gainclone is a joy to behold. Detail and presence would wipe the floor with the old QUAD.
My brother inherited my Dads 33/303 combo, and eventually replaced it with a CYRUS 7 (I think thats the number). I built a cheap knock up Gainclone for him and he said it gave the Cyrus a run for its money. The thing that let it down was a slight lack of bass control, this is easily solved by regulating the rails. So a cheap gainclone nearly matched a Cyrus, which was miles ahead of the Quad (which is in quiet retirement).
Shoog
My brother inherited my Dads 33/303 combo, and eventually replaced it with a CYRUS 7 (I think thats the number). I built a cheap knock up Gainclone for him and he said it gave the Cyrus a run for its money. The thing that let it down was a slight lack of bass control, this is easily solved by regulating the rails. So a cheap gainclone nearly matched a Cyrus, which was miles ahead of the Quad (which is in quiet retirement).
Shoog
Properly upgraded (i.e. replacement of 25 year old caps and re-biased) and with Net Audio's 303 PSU board the Quad 303 is ANYTHING but 'warm and woolly' as I wrote in Hi-Fi World about a year ago now. Any amp with caps which were never much cop to begin with and have aged will sound 'tired' as well - this isn't the 'sound' of the 303 but of the components!
However for sheer 'presence', REAL deep bass, startling fire-cracker dynamics and sheer life-like sounds I'm afraid it really does leave the dear old 303 standing. I practically rebuilt my tatty Quad 303 from scratch at one point (sticking to original component values apart from PSU and output caps) and put Black Gates on the circuit boards and hand-matched resistors etc etc etc, but the little Gainclonce just eclipses it in every respect. It doesn't sound like valve or solid-state, but rather a combination of the best virtues of both, if decent components are used and construction etc etc. I still live in hope that one day I'll be able to hear one of Peter Daniel's Patek SE amps - that must be pure audio nirvana!!!
Of course it depends what music one is into at the end of the day I guess and speakers used etc etc etc. All I can say is a properly sorted gainclone - for me at least - leaves behind most other amps I've ever heard regardless of price. They do need a bit of running in to sound at their best though and a source do do them justice...
- JohnM
However for sheer 'presence', REAL deep bass, startling fire-cracker dynamics and sheer life-like sounds I'm afraid it really does leave the dear old 303 standing. I practically rebuilt my tatty Quad 303 from scratch at one point (sticking to original component values apart from PSU and output caps) and put Black Gates on the circuit boards and hand-matched resistors etc etc etc, but the little Gainclonce just eclipses it in every respect. It doesn't sound like valve or solid-state, but rather a combination of the best virtues of both, if decent components are used and construction etc etc. I still live in hope that one day I'll be able to hear one of Peter Daniel's Patek SE amps - that must be pure audio nirvana!!!
Of course it depends what music one is into at the end of the day I guess and speakers used etc etc etc. All I can say is a properly sorted gainclone - for me at least - leaves behind most other amps I've ever heard regardless of price. They do need a bit of running in to sound at their best though and a source do do them justice...
- JohnM
I've heard the Quad ESL63 on a vast range of power amplifiers.
On the lower end of the price range here are just a couple:
Krell KSA50---Plinius SA50--Jean Hiraga JH50--JK Active I--Audiolabor Schnell--Denon 6600--Electrocompaniet Ampliwire 100--Luxman M05--Metaxas Iraklis--Yves Bernard André YBA2
Each one of these models blew the Quad 303 away, not to mention all the DIY amplifiers.
My preference goes to driving a Blower Bentley myself.
303s go for $60 overhere, and often not even busted ones.
I should have thought about this earlier. For $60 you can't build a nice case, let alone one with such beautifull alloy extrusion panels.
Sorry Choky, i'm gonna kill a few of your historic beauties.
Not for GC's though.
On the lower end of the price range here are just a couple:
Krell KSA50---Plinius SA50--Jean Hiraga JH50--JK Active I--Audiolabor Schnell--Denon 6600--Electrocompaniet Ampliwire 100--Luxman M05--Metaxas Iraklis--Yves Bernard André YBA2
Each one of these models blew the Quad 303 away, not to mention all the DIY amplifiers.
My preference goes to driving a Blower Bentley myself.
303s go for $60 overhere, and often not even busted ones.
I should have thought about this earlier. For $60 you can't build a nice case, let alone one with such beautifull alloy extrusion panels.
Sorry Choky, i'm gonna kill a few of your historic beauties.
Not for GC's though.
Sorry Choky, i'm gonna kill a few of your historic beauties.
Not for GC's though.
[/B]
hehe-be my guest!
one day you'll feel sorry.....
303s have a 2000uF output capacitor which was fine in the days of 8-15R loudspeakers, but inadequate with most modern 4R bass units.
The power supply was unusual with 4000uF of bulk cap, a npn pass transistor in the negative side (ie hi impedance before feedback) to give a regulated 67V with only 2.2uF of capacitance shared between both channels.
I suspect that the transformer was designed for >8R loads too
The power supply was unusual with 4000uF of bulk cap, a npn pass transistor in the negative side (ie hi impedance before feedback) to give a regulated 67V with only 2.2uF of capacitance shared between both channels.
I suspect that the transformer was designed for >8R loads too
I bought a 303 for fun, changed all larged aged elcos, made them a bit bigger and also changed the ones on the board for better ones and bypassed them with PPs. I also removed the input elco and used a PP instead.
This defnitely improved the amp, but I never did the net-audio PSU mod, though, or changed the pots, wiring, or put constant current sources here and there (see net-audio).
It sounded amazingly like Quad II but with firmer bass and more punch and detail...IMHO
Sold it on to a guy with ESL-57s, who called me after a couple of days and said the combo was perfect...
This defnitely improved the amp, but I never did the net-audio PSU mod, though, or changed the pots, wiring, or put constant current sources here and there (see net-audio).
It sounded amazingly like Quad II but with firmer bass and more punch and detail...IMHO
Sold it on to a guy with ESL-57s, who called me after a couple of days and said the combo was perfect...
Yes but what speaker ?
The 303 is an excellent amp when matched to the ESL57, from my
experience with this combination, it may well be the best amp for the ESL57.
It is pleasant but dated with other speakers ie JR149's , rather nice
with old AR's - but close to perfect with the ESL57.
Peter Walker realised direct coupling an amplifier to an ESL was not ideal. The 303 is a single ended design needing a output capacitor.
PW could just have easily built a dual rail amp at the time. For example try a Quad 405 with the best opamp etc compared to the 303 into the ESL57, the 303 wins hands down. PW already had
an exceptionally good speaker - had a good valve amp the Quad 2 and then made a great transistor amplifier for it.
How many contributers to this discussion about gainclone vs 303
are actally trying the gainclone with ESL57's ( the Door magically opens and everyone leaves ! )
Cheers / Chris
The 303 is an excellent amp when matched to the ESL57, from my
experience with this combination, it may well be the best amp for the ESL57.
It is pleasant but dated with other speakers ie JR149's , rather nice
with old AR's - but close to perfect with the ESL57.
Peter Walker realised direct coupling an amplifier to an ESL was not ideal. The 303 is a single ended design needing a output capacitor.
PW could just have easily built a dual rail amp at the time. For example try a Quad 405 with the best opamp etc compared to the 303 into the ESL57, the 303 wins hands down. PW already had
an exceptionally good speaker - had a good valve amp the Quad 2 and then made a great transistor amplifier for it.
How many contributers to this discussion about gainclone vs 303
are actally trying the gainclone with ESL57's ( the Door magically opens and everyone leaves ! )
Cheers / Chris
Re: Yes but what speaker ?
Well I've not tried a gain clone, but I've serviced on a couple of occasions ESL57's and 33/303 for a customer, he had a Thorens TD125AB as well, and I think a V15 cartridge.
It sounded VERY nice (even my wife liked it) - he also had a file of letters back and forth between him and Quad (Acoustic Manufacturing Co.) over the years.
The gentlemans name was Mr Rimmer, and I imagine he's probably dead by now (he was elderly last time I say him).
On the last occasion he asked me to replace the rectifiers in the ESL's, which he had sourced himself from Quad.
Chris Daly said:
Well I've not tried a gain clone, but I've serviced on a couple of occasions ESL57's and 33/303 for a customer, he had a Thorens TD125AB as well, and I think a V15 cartridge.
It sounded VERY nice (even my wife liked it) - he also had a file of letters back and forth between him and Quad (Acoustic Manufacturing Co.) over the years.
The gentlemans name was Mr Rimmer, and I imagine he's probably dead by now (he was elderly last time I say him).
On the last occasion he asked me to replace the rectifiers in the ESL's, which he had sourced himself from Quad.
Very Simple. I owned a 303 for years. I done every mod you could think of. I then made a gainclone for fun (There is a thread about it somewhere). It blew my quad out of the water, and is better than my old nap 160 by miles. Make it properly using the best components and a seperate power supply and voaila!!!! You can ditch the quad on ebay and make 3 gainclones!
Yes but what is the amp connected to ?
Are you using the Gainclone connected to ESL57's ? if so how does the Gainclone compare to the 303 ? The 303 is an excellent amp for driving ESL57's and only a handful of amps match well to that task including the naim 160. Peter Walker in retrospect did a pretty good job 40 years ago to design an amplifier that matched to Quads own speaker. It is interesting to have amp and speakers working harmoniously and this is what Quad did with this combination.
The many ESL57 users would be fascinated if the Gainclone offered a better sound than the 303, and would I am sure be interested in hearing from you
Cheers / Chris
Are you using the Gainclone connected to ESL57's ? if so how does the Gainclone compare to the 303 ? The 303 is an excellent amp for driving ESL57's and only a handful of amps match well to that task including the naim 160. Peter Walker in retrospect did a pretty good job 40 years ago to design an amplifier that matched to Quads own speaker. It is interesting to have amp and speakers working harmoniously and this is what Quad did with this combination.
The many ESL57 users would be fascinated if the Gainclone offered a better sound than the 303, and would I am sure be interested in hearing from you
Cheers / Chris
The 303 and ESL's are the special case which makes it worth having a 303.
Otherwise they are a bit stone age compared to many designs - including the gainclone.
Shoog
Otherwise they are a bit stone age compared to many designs - including the gainclone.
Shoog
I couldn't afford the ESL's at the time, so I can't comment on that. I find it hard to beleive that the 303's are better suited to these speakers than any other decent amp. Perhaps to a degree they are matched due to certain criteria like output power etc. but surely so are many others. I use Linn speakers on my gainclone. I was told they were best suited to my naim. That simply isn't true! The best advice I can offer is to make a gainclone and try the ESL's on it. What have you got to lose. Less than £100 will prove the point, then sell whatever doesn't suit.
barry.childs said:
I suspect this is not a very good advice unless you really want to test the protection circuit in the little chips. GCs sound good only with really easy loads.
barry.childs said:
If I had the 303's I'd keep them as is or rebuild them, they're far to nice to cannibalise. I've owned a 405 and still have a 606 which I occasionally use for sub-woofer driving. The Quads have nothing wrong with them, they sound a little bit `dead' compared with better amps that I've tried.
I bought a pair of ESL57's a few years ago and killed a few amps driving them which resulted in the necessity of lashing up a quick replacement using some LM3886's I possessed. I was'nt disappointed, they were very capable of driving them with good results. Having some LM1875's and being worried about overloading the Quads, I used them with a pair of 12v smps's per chip. I was even more surprised how good they sound, far better than the LM3886's. I'm putting together a JLH Class A in the future - Iwill be very happy if it improves on the 1875's ...
Mick.
- Status
- Not open for further replies.